Until the day comes that this miraculous occurrence, this feat of pure paranormality is sufficiently explained, and not through fraudulent investigations and perverted science, I will assume WTC 7 was, in the words of professor emeritus Hugo Bachmann:

I would go so far, contra Joshi (and contra Farnsworth Wright, who rejected "The Shunned House" when Lovecraft submitted it to Weird Tales) as to say that the slow, labored buildup of historical and spectral details and the equally dense justification that the modern, scientific Whipple narrator gives for the continuing horrors are both structurally necessary for the narrative (especially the pacing) to work correctly and thematically necessary for the transmission of the exact weird sensation -- of paranormality, not supernaturalism -- that Lovecraft intends.